ASSOCIATION	ABBREVIATION	AREA
Conference of Independent Schools Athletic Association	CISAA	Ontario Independent schools as defined by the Conference
Central Ontario Secondary Schools Association	COSSA	The counties of Haliburton, Northumberland, Hastings, Peterborough, Victoria, and Prince Edward.
Central Western Ontario Secondary Schools Association	CWOSSA	The counties of Bruce, Grey, Dufferin, Waterloo, Brant, Norfolk and Wellington.
Eastern Ontario Secondary Schools Athletic Association	EOSSAA	The counties of Renfrew, Frontenac, Lanark, Leeds and Grenville, Stormont Dundas and Glengarry, Prescott and Russell, and Lennox and Addington.
Georgian Bay Secondary Schools Association	GBSSA	The county of Simcoe, the districts of Muskoka and Parry Sound.
Golden Horseshoe Athletic Conference	GHAC	The County of Halton and schools within the Hamilton-Wentworth Catholic District School Board.
Lake Ontario Secondary Schools Association	LOSSA	The region of Durham plus Courtice Secondary School, Bowmanville High School, and St. Stephen's Secondary School in Bowmanville.
National Capital Secondary Schools Athletic Association	NCSSAA	The city of Ottawa.
North Eastern Ontario Athletic Association /Association athlétique du nord-est de l'Ontario	NEOAA/AANEO	The districts of Cochrane and Timiskaming.
Northern Ontario Secondary Schools Association	NOSSA	The districts of Manitoulin, Sudbury, Algoma, Nipissing and the regional municipality of Sudbury.
North Western Ontario Secondary Schools Athletic Association	NWOSSAA	The districts of Kenora, Rainy River, Thunder Bay and Patricia.
Region of Peel Secondary Schools Athletic Association	ROPSSAA	The regional municipality of Peel and schools within the Dufferin-Peel Catholic District School Board.
Southern Ontario Secondary Schools Association	SOSSA	The regional municipality of Niagara South, the counties of Haldimand, Lincoln and the schools within the Hamilton-Wentworth District School Board.
South Western Ontario Secondary Schools Athletic Association	SWOSSAA	The counties of Essex, Kent and Lambton.
Toronto District College Athletic Association	TDCAA	Catholic high schools within the City of Toronto, and independent high schools within the boundaries of the City of Toronto not operated under the regular Ministry of Education Boards in the area, but not those which are members of the CISAA..
Toronto District Secondary School Athletic Association	TDSSAA	Public high schools within the City of Toronto.
Western Ontario Secondary Schools Athletic Association	WOSSAA	The counties of Huron, Perth, Middlesex, Elgin and Oxford.
York Region Athletic Association	YRAA	The region of York.